1. Patients diagnosed with other types of respiratory infections (non-COVID-19). 2. Patients with a current tracheostomy or laryngectomy. 3. Patients who are receiving concomitant respiratory therapy such as oxygen, positive airway pressure, or ventilator support. 4. Patients who use nasal steroids such as fluticasone, budesonide, mometasone, and/or triamcinolone. 5. Patients who need hospitalization for reasons other than COVID-19 infection. 6. Patients who are unable to self-administer the nasal spray as prescribed. 7. Females who are breastfeeding, pregnant, or planning or attempting to become pregnant. 8. Patients diagnosed with COVID-19 for more than 3 days before randomization. 9. Patients who are mentally or neurologically disabled, and severe anxiety. 10. Patients who have any severe respiratory disease such as lung disease, traumatic thoracic injury, had a history of lung surgery, had liver or kidney disease therapy, or who are receiving concomitant liver or kidney disease therapy. 11. Patients with an allergic reaction to Hypromellose and/or nitric oxide

1. Patients diagnosed with other types of respiratory infections (non-COVID-19). 2. Patients with a current tracheostomy or laryngectomy. 3. Patients who are receiving concomitant respiratory therapy such as oxygen, positive airway pressure, or ventilator support. 4. Patients who use nasal steroids such as fluticasone, budesonide, mometasone, and/or triamcinolone. 5. Patients who need hospitalization for reasons other than COVID-19 infection. 6. Patients who are unable to self-administer the nasal spray as prescribed. 7. Females who are breastfeeding, pregnant, or planning or attempting to become pregnant. 8. Patients diagnosed with COVID-19 for more than 3 days before randomization. 9. Patients who are mentally or neurologically disabled, and severe anxiety. 10. Patients who have any severe respiratory disease such as lung disease, traumatic thoracic injury, had a history of lung surgery, had liver or kidney disease therapy, or who are receiving concomitant liver or kidney disease therapy. 11. Patients with an allergic reaction to Hypromellose and/or nitric oxide